1. Field of the Invention
The present invention relates to an anti-G suit simulation system and especially pertains to an arrangement or system for simulating realistic acceleration conditions which are normally encountered during strenuous maneuvers carried out by pilots operating high-performance aircraft, such as jet fighter aircraft. More particularly, the invention pertains to an anti-G simulation system wherein aircraft simulator pilots are exposed to physical conditions which rapidly and faithfully simulate and compensate for changes in high-intensity accelerations and gravitational effects or so-called G-conditions which are ordinarily encountered by the pilots of high-performance aircraft during the execution of aircraft maneuvers.
During the operation of high performance aircraft, such as jet fighter aircraft or the like, in the implementation of flight maneuvers in which the aircraft rapidly and dramatically deviates from a normally horizontal path of flight, for instance, during steep climbs and descents, pilots are generally subjected to the physical effects of intense or high gravitational forces, generally referred to as G-forces, as a result of the extreme accelerations carried out by the changes in speed and direction of travel of the aircraft, which, in the absence of protective measures, may lead to serious physical and potentially even fatal consequences to the pilot of the aircraft. These conditions may evidence themselves as so-called grayouts or blackouts due to a loss of the flow of blood to the pilot's head, resulting in possible loss of orientation with consequent impairment of pilot judgement, loss of consciousness and control over the aircraft in view of the high-performance aircraft sustaining gravitational forces of up to 9 G (9 times the force of gravity) or even higher within a span of time of only a few seconds because of the intense maneuvers. These physical phenomena or conditions which are encountered by a pilot when pulling back hard on an aircraft control stick in order to accomplish a rapid climb or descent or to implement a fast banking turn, pose the danger to the pilot of a loss in combat effectiveness, and are frought with the danger of potentially fatal results.
In order to counteract the deleterious physical effects due to extreme or intense G-forces to which pilots are subjected during the rapid and high-speed maneuvers of such high-performance aircraft, in the aircraft and aerospace technology there have been developed anti-G suits (also designated as G-suits) which have presently reached a high degree of sophistication. Such anti-G suits, which have been in widespread use for many years, particularly in military aviation and aerospace applications, are pressurized at controlled rates in correlation with the variable G-forces acting on the pilot wearing the G-suit, so as to rapidly counteract any potentially harmful physical effects which may be produced through the G-forces generated by the high speed maneuvers of the aircraft. Reversely, as the G-forces acting on the aircraft, and resultingly on the pilot, are lessened due to the aircraft being maneuvered into more level flight, the pressure in the anti-G suit is correspondingly reduced so as to impart to the pilot a physical condition at which the pressure of the G-suit conforms to a basic G-force; in effect, normal gravity.
For purposes of pilot training and physical and psychological conditioning, in order to simulate the G-force responsive conditions effectuated in the pressurization of anti-G suits worn by pilots, whereby such conditions are normally encountered by pilots during actual flight in implementing high-speed maneuvers of high-performance aircraft, there have been developed flight simulators which attempt to duplicate the actual conditions of flight of intensely maneuvering aircraft under rapidly changing G-forces so as to enable pilots to develop a "feel" for the accelerations and quickly varying high G-forces which are normally encountered during the operation of the high-performance aircraft without actually subjecting a pilot and aircraft to the dangerous risks derived from those G-forces. Although state-of-the-art anti-G suit flight simulators and attendant control systems for operating the simulators are technologically advanced in meeting the basic requirements in the generating of simulated high-performance flight conditions and resultant G-forces which are ordinarily imposed on aircraft pilots, these currently employed simulators are still subject to the limitations in that the simulation systems have been unable to duplicate actual conditions in varying and relieving the pressures which have been generated and reign in the anti-G suits during periods when the aircraft (or simulated aircraft) reverts to normal level flight from preceding high G-forces which are due to rapid high-speed maneuvers. Although these conditions should be ideally attainable through a rapid and controlled evacuation of or regulation of the pressure reigning in the anti-G suit; for instance, in correlation with the reducing G-forces signifying return of the simulated condition of the aircraft flight simulator to normal or level aircraft flight, in actual practice a satisfactory level of control or pressure regulation in evacuating the anti-G suit has not yet been fully achieved in the current flight simulator technology.
2. Discussion of the Prior Art
Although various patents are currently existent which address themselves to alleviating the problems due to G-forces which are imposed on the pilots of high-performance aircraft, and also to the close simulation thereof, these have not yet fully met the requirements of providing ideally simulated aircraft performance characteristics in anti-G suits worn by pilots.
Ashworth U.S. Pat. No. 4,164,079 discloses an aircraft seat cushion which is controllably inflatable in response to realistic acceleration cues imparted to an aircraft simulator pilot. Although the seat cushion is inflated at controlled rates in conformance with simulated acceleration conditions to which an aircraft pilot may be subjected, there is no disclosure of a similarly controlled simulation of aircraft performance during rapid deceleration or reduction of such G-forces necessitating concomitant controlled evacuation of the seat cushion.
Armstrong U.S. Pat. No. 4,895,320 discloses a control system for an anti-G suit functioning in conformance with the performance or maneuvers carried out by a high-performance aircraft. Again, there is no disclosure of an anti-G suit simulation system wherein the simulated acceleration maneuvers and also the deceleration aspects of a high-performance aircraft are closely duplicated in regulating the pressure conditions reigning in the anti-G suit.
Van Patten U.S. Pat. No. 4,736,731 discloses a rapidly acting electro-pneumatic anti-G suit control valve which is utilized in an installation for controlling the inflation rate of an anti-G suit. However, there is no disclosure of a system for correlating all of the conditions encountered during the deflation or evacuation of the anti-G suit at a controlled rate in close conformance with rapid changes in G-forces acting on a simulation pilot to an extent which would provide ideal simulation characteristics of actual aircraft performance and physical effects encountered by the pilot.